1. Field of the Invention
The present invention relates to an optical element that limits the progression of light in directions that are oblique with respect to a surface, and to a lighting device, a display device and an electronic device that use this optical element.
2. Description of the Related Art
It is in some cases desirable that persons other than the user of a display device are not able to view the display screen. For this purpose, an optical element in the form of film for limiting the progression of light in directions oblique to the surface is known, and such an optical element is referred to as a “micro-louver.”
As shown in the publication JP-A-S50-092751 of FIG. 1, relevant micro-louver 200 has a structure in which each of light-absorption portions 202 and each of transparent portions 203 are alternately laminated, each of the portions 202 and 203 extending perpendicular to surface 201. This micro-louver 200 is arranged on a display surface of a display device, and the light, which is emitted in an oblique direction to the display surface, is limited, such that a display image cannot be viewed from the oblique direction to the display surface.